Suppression of <i>Phytophthora</i> on <i>Chamaecyparis</i> in Sustainable Horticultural Substrates Depends on Fertilization and Is Linked to the Rhizobiome

Nature management residues (i.e., biomass generated from the of nature reserves) are promising peat alternatives for horticultural substrates and may have a positive effect on disease suppression because their microbiological characteristics. Moreover, addition fertilizer also affect rhizosphere microbiome and, accordingly, suppression. In this study, we determined two in chopped heath acidified soft rush) fertilization regimes pure nitrogen compound fertilizer) Phytophthora spp. Chamaecyparis lawsoniana. The bacterial fungal community was characterized using 16S ribosomal RNA internal transcribed spacer 2 gene metabarcoding. Soft rush with (R2) (H1) showed disease-suppressive largest shifts microbial composition compared peat-based substrates. treatments differences communities. Different genera associated described biocontrol agents were found higher amounts those treatments. Aspergillus Trichoderma highly abundant H1, while Actinomadura Bacillus had high abundance R2. addition, relative abundances 24 9 negatively correlated severity. Several genera, including Bacillus, Chaetomium, Actinomadura, significantly more one This study shows that suppressiveness sustainable is dependent can be linked to changes